Unable to find default app

Most of the apps that I try to download on my playbook from place other than bberry appworld don't go thru, even though the originator ensures me that I should be able to download it. the download never seems to start, just the ”download complete" message pops up - literally immediately after I click "save file", no line indicating the progress of download. When I click to open the downloaded file, get message "unable to find default app". Do I need to change any settings to be able to download?

Chances are if your not getting your apps through BlackBerry World. Or side loading an Android app. Then they won't work. Yes your PB will sometimes accept the download but you will not be able to install it. Check your files app and see if the file is there. If the file is there then the dev is right you did complete the download. You are just unable to install. Then the question to the dev would be is it BlackBerry compatible?

Terrsamy, thank for your response. For example, I tried to download Skype from the bberry Site. (sorry cannot post links)
Also, I was trying to download apps from IG Index. It detects that I'm mobile and offers to download app...When I look for it in the Bberry world, it says "this item is not supported your current device profile"

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Walter66, thank you for your response. None of the downloads shows up in the file folder, and the apps I'm trying to get are supposed to be for Playbook.